Diablo III will feature old standards such as the quotable Deckard Cain, as well as a new version of Tristram and a fresh class dubbed the Witch Doctor. The jungle-born warrior will use ancient tribal magic to cast disease and mind control spells, in addition to utilizing pets such as locust swarms and mongrels.
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The game will also include several control improvements, including full zoom capability and a hotbar to easily access skills. Players will be able to quickswap between skills using the mouse wheel or tab key.

Armor will now be class-specific, designed to provide each character a unique look. Classes themselves are more diverse, as it was noted that there will be female versions of both the Barbarian and Witch Doctor.

In a demo of the Barbarian class, the company noted that less of an emphasis will be placed on potions for health. Instead, red orb-like items will drop that immediately recover health once the player picks them up.

Environmental destruction was also shown off, with a character at one point busting through a solid wall. The environment can also be used to kill enemies, as in the case of objects that fell from a wall, killing a group of monsters.

Enemies were shown to be larger in scale than in past games, with giant evil trees and a massive demon called a Siegebreaker.

Blizzard has released a set of official features and a story description, which can now be conveniently viewed below the fold:

Two decades have passed since the demonic denizens, Diablo, Mephisto, and Baal, wandered the world of Sanctuary in a vicious rampage to shackle humanity into unholy slavery. Yet for those who battled the Prime Evils directly, the memory fades slowly and the wounds of the soul still burn.

When Deckard Cain returns to the ruins of Tristram's Cathedral seeking clues to new stirrings of evil, a comet from the heavens strikes the very ground where Diablo once entered the world. The comet carries a dark omen in its fiery being and it calls the heroes of Sanctuary to defend the mortal world against the rising powers of the Burning Hells--and even the failing luminaries of the High Heavens itself.

Experience the intensity of multiplayer Diablo III over an all-new, wickedly-enhanced Battle.net platform with numerous enhancements to make connecting with your friends easier--and cooperative gameplay more fun.